Spectrum of ST amplitude: athletes and an ambulatory clinical population

Background and PurposeTo augment data guiding thresholds for myocardial ischemia and cardiac risk, we studied resting ST amplitude in ambulatory patients and collegiate athletes.MethodsWe analyzed 4041 ECGs from ambulatory visits at the Veterans Affairs in Palo Alto, California from 1997 to 1999 and 1114 screening ECGs from Stanford University athletes in 2007–2008. Using the PR interval as the isoelectric line and > 95 μV and < − 45 μV (visually equivalent to 1 mm and 0.5 mm) to define ST elevation and depression, ST amplitude was measured at QRS-end.ResultsST elevation was most prevalent in males, African Americans, and athletes (87% of male athletes in anterior leads). ST depression was rare in athletes and, among patients, associated with time to cardiovascular death in lateral leads (age-adjusted HR of 1.9, p < 0.001).ConclusionsST amplitude differs by gender, age, race, and athletic status, which should be considered when developing guidelines for ECG interpretation.